The present invention relates to a front air-rectifying structure of an automotive vehicle which comprises a shutter unit to control a flow of outside air which flows into an engine room through a grille opening portion formed at a vehicle front portion, for example.
The front portion of the automotive vehicle is configured to take in the outside air into the engine room through the grille opening portion formed at a bumper face, thereby cooling a heat exchanger, such as a radiator or intercooler, as well as an engine. Further, in these days, the automotive vehicle which is provided with the shutter unit to control the flow of the outside air flowing in through the grille opening portion for achieving further improvement of the fuel economy or reduction of exhaust gas is known.
The shutter unit comprises plural flaps which are opened or closed in accordance with a temperature of lubricant oil or cooling water which circulates in the engine, or a vehicle speed. For example, the shutter unit can stop a supply of the outside air to the heat exchanger or the engine by closing the flaps. Thereby, the lubricant oil or cooling water can be heated up to a desired temperature quickly, thereby suppressing deterioration of the fuel economy which may be caused by a so-called warming-up operation.
In the meantime, the shutter unit can suppress the flow of the outside air into the engine room by controlling the flaps according to the vehicle speed, thereby suppressing generation of turbulence which may be caused by merging of the outside air flowing down rearward from the engine room with traveling air flowing down along a vehicle side portion. Thereby, an increase of traveling resistance which may be caused by the turbulence is suppressed, thereby achieving the improvement of the fuel economy or the reduction of exhaust gas.
European Patent Application Publication No. 2335963 A1 discloses, as an example of the above-descried shutter unit, an airflow device 11 which comprises a shutter mechanism including plural openable flaps (fins 17), an air guide member (a duct 22) to guide outside air flowing in through a grille opening portion (a grille 21), and a drive mechanism portion (a link mechanism 24 and a torque motor 26) to drive the flaps for opening or closing, for example.
Meanwhile, the shutter unit of the above-described patent document is configured to have a rather long length in a vehicle width direction from requirements of a vehicle-body design or structure, so that the length, in the vehicle width direction, of the air guide member may become rather long as well.
Further, there may be a situation in which a vehicle-body vibration due to unevenness of a road surface or pressure fluctuation of the outside air flowing in through the grille opening portion acts on the air guide member. Accordingly, the rigidity of a lower portion or an upper portion of the air guide member becomes low easily, so that the lower or upper portions of the air guide member may be made to vibrate greatly by the vehicle-body vibration or the pressure fluctuation.
When the vibration of the air guide member is transmitted to the shutter unit, an unintentional load may be added to a flap support portion supporting the flaps or an opening/closing mechanism portion. Accordingly, there is a concern that a position shift of the flaps or an improper move of the opening/closing mechanism portion may occur, so that some problem may happen to the opening/closing move of the flaps.